Tail docking is a very cruel and outdated procedure. Known as a caudectomy when it is medically necessary; such as from a tumor or a severely injured tail. The term "docking" is purely cosmetic. 

According to Notabully.org

"Clearly, docking your dogs tail could lead to a reduction in their balance and movement.

Much worse though is that tail docking can lead to long-term pain, according to recent research from Scotland’s Rural College and Newcastle University.

Another study concluded that the negative effects tail-docking has on a Boxer’s ability to communicate are much stronger than previously realized. Furthermore, it found that dogs with docked tails suffer heightened ongoing pain sensitivity and negative welfare impacts that will be life-long."

Peta has this to say in regards to tail docking

"Dogs usually have their ears cropped when they are just 8 to 12 weeks old. At this stage in their development, the trauma of the procedure can have a strong psychological impact on the maturing pup. The process of taping and retaping a pup’s ears to force them to stand erect after they have been cropped can be agonizing for the dog.

Puppies are normally just a few days old when their tails are docked. They are generally not even given anesthetics to numb the pain. Compassionate veterinarians object to the arbitrary removal of body parts used for communication, balance, and expression. Dogs “talk” to their human companions and other dogs using their ears and tails.

Performing medically unnecessary procedures that simply perpetuate the image of dogs as fashion accessories is outrageous. This image is promoted by the American Kennel Club at its canine beauty pageants and by breeders who believe that “their” breed will be “ruined” if it does not maintain the image handed down by parent breed clubs decades ago.

These procedures are so cruel that they are banned in many European countries. For example, British kennel clubs outlawed ear-cropping a century ago, and cosmetic tail-docking was stopped the U.K. in 1993."

With this procedure banned in MANY other countries, WHY are we still doing this here!!??